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21.
The production of a notable and highly effective pectinase by the local fungal strain Aspergillus carneus NRC1 utilizing the abundant Egyptian orange peels and pulps (OPP) scraps excluded in the orange juice and canning industry was achieved in 5-day submerged fermentation (SMF) cultures, at temperature and pH ranges of 30–55 °C and 5.0–5.5, respectively. Fresh or thawed OPP (6%, w/v) were the most preferable sole carbon source. Pectinase activity was dramatically stimulated by ammonium sulphate as the sole nitrogen source, and at the same time strongly inhibited the production of the other tested enzymes, i.e., cellulases and hemicellulases. The lyophilized enzyme preparation was free from any ochra or aflatoxins. The optimum conditions of this methodology including enzyme and substrate (citrus pectin) concentrations were 40 mg ml?1 and 7% (w/v), respectively, with pH and temperature of 4.0 and 55 °C, respectively.  相似文献   
22.
Abstract

L-glutaminase from bacterial sources has been proven to be effective and economical agents in cancer therapy, food industry and high-value chemicals like threonine. In the present study, a newly isolated bacterial strain was potentially producing extracellular L-glutaminase, it identified as Bacillus subtilis OHEM11 (MK389501) using the 16S rRNA gene. L-glutaminase production optimized and the optimum factors for production under submerged fermentation were at pH 6.5–7.0 and 35?°C after 28?hr using rhamnose and glutamine as carbon and nitrogen sources, respectively, while bagasse was the best inducer for the production under solid-state fermentation. Ethanol precipitation and ion-exchange chromatography using QFF are the purification steps. L-glutaminase was purified to 2-fold with specific activity 89.78?U/mg and its molecular weight about 54.8?kDa with the alkaline property of the enzyme makes it clear having carcinostatic property; maximum enzyme activity at pH 8.2 and 40?°C and retained about 90% activity for 1?hr. The cytotoxicity effect of L-glutaminase indicated a significant safety on Vero cells with high anticancer activity against NFS-60, HepG-2, and MCF-7 cancer cell lines. The outcomes demonstrated that L-glutaminase could be applied in many biotechnological applications such as pharmaceutical and food processing.  相似文献   
23.

Iron deficiency is a common etiology of anemia that causes suboptimal response to erythropoietin therapy in hemodialysis (HD) patients. This study investigated the association between vitamin D receptor (VDR) genetic variant (FokI) rs2228570 with iron indices (serum iron, transferrin, transferrin saturation, and ferritin). Sixty adequately hemodialyzed patients subdivided into two groups; 31 patients with transferrin saturation (TSAT)?<?20% and 29 with TSAT?>?20% who received I.V sodium ferric gluconate, calcium, and vitamin D. Sixty normal healthy were selected as the control group.. VDR genetic variant (SNP rs2228570) was genotyped in all subjects using PCR/RFLP. HD patients showed a higher frequency of rs2228570 FF genotype (38.3%) than controls (31.7%). The frequency of ff genotype and f allele in patients (8.4 and 35% respectively) were significantly lower than controls (25 and 46.7% respectively). Allele model (f vs. F): OR 0.721, 95% CI 0.521–0.998, P?=?0.049. While (ff vs. FF): OR 0.452, 95% CI 0.223–0.917, P = 0.028. The distribution of Ff?+?ff genotypes in HD cases with TSAT?>?20% was higher than in HD cases with TSAT?<?20%, Dominant model (Ff +ff vs FF): OR 2.753, 95% CI 1.902–3.409, P?=?0.048. f allele showed lower frequency in low TSAT group than high TSAT group (27.4 vs. 43.1%) with significant P value (P?=?0.042) with allele model (f vs. F): OR 2.012, 95% CI 1.923–4.226, P?=?0.042. Fok-1 ff, Ff?+?ff genotypes were significantly associated with TSAT?>?20% with a protective effect against low TSAT in HD patients.

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24.
Nitric oxide (NO) and calcium channel blockers are two agents that can affect gastrointestinal motility. The goal of this work was to study the rabbit intestinal smooth muscle contraction response to (1) sodium nitroprusside (SNP), the NO donor, and its potential mechanism of action, and (2) nifedipine, the l-type Ca2+ channel blocker; to clarify the degree of participation by extra- and intracellular Ca2+ in smooth muscle contraction. We used standard isometric tension and intracellular micro-electrode recordings. To record the activity of the longitudinal smooth muscle of the ileum, segments of 1.5?cm length of the ileum were suspended vertically in organ baths of Krebs solution. The mechanical activity of the isolated ileal longitudinal muscle was recorded. Different substances were added, and the changes produced on spontaneous contraction were recorded. We found that SNP produced significant decrease, while nitric oxide synthase inhibitor produced significant increase in the amplitude of spontaneous contractions. Both apamin, the Ca2+-dependent K+ channel blocker, and methylene blue, the inhibitor of soluble guanylate cyclase, alone, partially decreased relaxation induced by SNP. Addition of both methylene blue and apamine together abolished the inhibitory effect produced by SNP on spontaneous contractions. Nifedipine produced significant decrease in the amplitude of spontaneous contractions. In conclusion, in longitudinal muscle of rabbit ileum, calcium channels blocker are potent inhibitors of spontaneous activity. However, both extracellular and intracellular Ca2+ participates in the spontaneous contractions. NO also has inhibitory effect on spontaneous activity, and this effect is mediated by cGMP generation system and Ca2+-dependent K+ channels.  相似文献   
25.
This report is of a round-table discussion held in Cardiff in September 2009 for Cesagen, a research centre within the Genomics Network of the UK??s Economic and Social Research Council. The meeting was arranged to explore ideas as to the likely future course of human genomics. The achievements of genomics research were reviewed, and the likely constraints on the pace of future progress were explored. New knowledge is transforming biology and our understanding of evolution and human disease. The difficulties we face now concern the interpretation rather than the generation of new sequence data. Our understanding of gene-environment interaction is held back by our current primitive tools for measuring environmental factors, and in addition, there may be fundamental constraints on what can be known about these complex interactions.  相似文献   
26.
Seventy isolates belonging to 6 species and one variety of A. flavus group were shown to degrade the progesterone side-chain to yield delta 4-androstene-3,17-dione and testosterone. The isolates of five species (A. flavo-furcatis, A. flavus, A. oryzae, A. parasiticus and A. tamarii) possessed enzyme systems catalyzing the opening of ring D and formed testololactone as final steroid metabolite in addition to their ability to produce the above mentioned two products. 11 beta-Hydroxy-delta 4-androstene-3,17-dione was formed by only A. flavus and A. tamarii while 11 beta-hydroxytestosterone was produced by A. flavo-furcatis, A. parasiticus and A. subolivaceus. The chromatographic resolution of the mixture products obtained (when the selective isolate of each species reacted with 1 g of progesterone) revealed that 60-75% of progesterone was converted into delta 4-androstene-3,17-dione (8-30%), testosterone (7-33%), testololactone (14-37%) and other products (3-40%). The most bioconversion activity was exhibited by A. oryzae, followed by A. parasiticus. The highest values of delta 4-androstene-3,17-dione (30% of added progesterone) and testosterone (33%) were formed by A. flavus var. columnaris while those of testololactone (37%) were produced by A. oryzae. A systematic variation could be observed between the different tested species of A. flavus group with respect to the transformation reactions of progesterone. Comparative biotransformation results showed that essential differences exist between the tested species in this group; this biochemical differentiation may supplement the morphological and other physiological criteria used in the identification of the different species in the A. flavus group.  相似文献   
27.
BackgroundTo date, the cause of inflammatory bowel disease (IBD) remains a mystery. A balance between cell proliferation and apoptosis maintains intestinal tissue homeostasis. Dissociation-induced myosin-actin contraction results in stem cell apoptosis. This study aiming to evaluate the influence of the myosin heavy chain 9 (MYH9) gene single nucleotide polymorphisms (SNPs) on inflammatory bowel disease.Subjectsand methods: The study carried on eighty patients with IBD and seventy controls. All participants subjected to history taking, thorough physical examination, colonoscopy and laboratory investigations. Genotyping performed for rs4821480 and rs3752462 by SNP assay real-time PCR methods.ResultsOn analyzing rs3752462 CT and TT genotypes were significantly more frequent in IBD patients as compared to controls with 4.6 fold increase in the risk of IBD. While on analyzing rs4821480, The TG and GG genotypes have significant increased distribution among the IBD patients as compared to the controls with 5.3 fold increase in the risk of IBD and higher prevalence of GG genotype in patients with low hemoglobin level and higher BMI.ConclusionThe rs3752462 T allele and rs4821480 G allele of MYH9 are associated with more susceptibility to IBD.  相似文献   
28.
Fascioliasis is one of the public health problems in the world. Cysteine proteinases (CP) released by Fasciola gigantica play a key role in parasite feeding, migration through host tissues, and in immune evasion. There has been some evidence from several parasite systems that proteinases might have potential as protective antigens against parasitic infections. Cysteine proteinases were purified and tested in vaccine trials of sheep infected with the liver fluke. Multiple doses (2 mg of CP in Freund's adjuvant followed by 3 booster doses 1 mg each at 4 week intervals) were injected intramuscularly into sheep 1 week prior to infect orally with 300 F. gigantica metacercariae. All the sheep were humanely slaughtered 12 weeks after the first immunization. Changes in the worm burden, ova count, and humoral and cellular responses were evaluated. Significant reduction was observed in the worm burden (56.9%), bile egg count (70.7%), and fecel egg count (75.2%). Immunization with CP was also found to be associated with increases of total IgG, IgG(1), and IgG(2) (P<0.05). Data showed that the serum cytokine levels of pro-inflammatory cytokines, IL-12, IFN-γ, and TNF-α, revealed significant decreases (P<0.05). However, the anti-inflammatory cytokine levels, IL-10, TGF-β, and IL-6, showed significant increases (P<0.05). In conclusion, it has been found that CP released by F. gigantica are highly important candidates for a vaccine antigen because of their role in the fluke biology and host-parasite relationships.  相似文献   
29.
Chromium deficiency is associated with impaired glucose tolerance (IGT) and dyslipidemia. Hence, the objective of the current study was to investigate chromium status among Saudi men with and without established cardiovascular disease (CVD) and its relationship to glucose tolerance, lipid profile and other established CVD risk factors. We measured serum and urine chromium concentrations, fasted lipid profile, plasma glucose, and serum lipid peroxide in 130 Saudi men with an established history of myocardial infarction and 130 age-matched controls without established CVD. Patients with established CVD had higher serum triglycerides (p < 0.05) and plasma glucose (p < 0.0001) and lower serum and urinary chromium concentrations (p < 0.0001) than controls. Serum chromium was inversely correlated with plasma glucose among cases and controls (r = −0.189, p < 0.05 and r = −0.354, p < 0.00001, respectively). Plasma glucose (OR 1.127, CI 1.0–1.269, p < 0.05), serum chromium (OR 0.99, CI 0.985–0.995, p < 0.0001), and urinary chromium (OR 0.988, CI 0.981–0.995, p < 0.001) were independently associated with the presence of established coronary disease applying this model. While chromium metabolism appears to be altered in individuals with CVD, it is unclear whether chromium supplementation would be effective in CVD prevention among patients with IGT. This would need to be tested in long-term outcome trials.  相似文献   
30.
Acinetobacter baumannii (A. baumannii) is one of the most common Gram-negative pathogens that represent a major threat to human life. Because the prevalence of Multidrug-resistant biofilm-forming A. baumannii is increasing all over the world, this may lead to outbreaks of hospital infections. Nonetheless, the role of raw meat as a reservoir for A. baumannii remains unclear. Here our research was aimed to exhibit the frequency, precise identification, and genotyping of biofilm-related genes as well as antimicrobial resistance of A. baumannii isolates of raw meat specimens. Fifty-five A. baumannii strains were recovered from 220 specimens of different animal meat and then identified by Peptide Mass Fingerprinting Technique (PMFT). All identified isolates were genotyped by the qPCR method for the existence of biofilm-related genes (ompA, bap, blaPER-1, csuE, csgA, and fimH). In addition, the antimicrobial resistance against A. baumannii was detected by the Kirby-Bauer method. Based on our findings, the frequency rate of 55 A. baumannii isolates was 46.55%, 32.50%, 15.00%, and 9.68% of sheep, chicken, cow, and camel raw meat samples, respectively. The PMFT was able to identify all strains by 100%. the percentages of csuE, ompA, blaPER-1, bap, and csgA genes in biofilm and non-biofilm producer A. baumannii were 72.73%, 60%, 58.2%, 52.74%, and 25.45%, respectively. In contrast, the fimH was not detected in all non-biofilm and biofilm producer strains. The ompA, bap, blaPER-1, csgA were detected only in biofilm-producing A. baumannii isolates. The maximum degree of resistance was observed against amoxicillin/clavulanic acid (89.10%), gentamicin (74.55%), tetracycline (72.73%), ampicillin (65.45%), and tobramycin (52.73%). In conclusion, our investigation demonstrated the high incidence of multi-drug resistant A. baumannii in raw meat samples, with a high existence of biofilm-related virulence genes of ompA, bap, blaPER-1, csgA. Therefore, it has become necessary to take the control measures to limit the development of A. baumannii.  相似文献   
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